Various people will speak, including the DZO, DZM, S&TA and Jump Pilot. If that happens to be you, be sure and write down at least an outline of what you want to speak about.
As pilots we are taught that safety is #1, so do not simply stand up and say a couple words. Take advantage of the fact that you have everyone's attention on the topic of safety. Personally, I usually talk about Weight & Balance, Safety Belts, Emergency Procedures (ie. departure/en route climb engine out) and Prop Awareness during hot fueling, to name a few.The only problem with Safety Day is that it's only one day a year. If I owned a drop zone we would have safety meetings every month.